以下代码以光标所在位置为中心,在全屏幕上绘制一个十字架:
procedure TForm1.Button1Click(Sender: TObject);
var
FullscreenCanvas:TCanvas;
DC:HDC;
begin
DC:=GetDC(0);//取得屏幕的DC,参数0指的是屏幕
FullscreenCanvas :=
TCanvas.Create;//创建一个CANVAS对象
FullscreenCanvas.Handle := DC;
//将画布关联到屏幕句柄,以便能做图
FullscreenCanvas.MoveTo(mouse.CursorPos.X,0);
FullscreenCanvas.LineTo(mouse.CursorPos.x,768);
FullscreenCanvas.MoveTo(0,Mouse.CursorPos.Y);
FullscreenCanvas.LineTo(1024,Mouse.CursorPos.y);
end;
以下代码在全屏幕中心绘制一个十字架:
procedure TForm1.Button1Click(Sender: TObject);
var
FullscreenCanvas:TCanvas;
DC:HDC;
begin
DC:=GetDC(0);//取得屏幕的DC,参数0指的是屏幕
FullscreenCanvas :=
TCanvas.Create;//创建一个CANVAS对象
FullscreenCanvas.Handle := DC;
//将画布关联到屏幕句柄,以便能做图
FullscreenCanvas.MoveTo(screen.Width div 2,0);
FullscreenCanvas.LineTo(screen.Width div 2,768);
FullscreenCanvas.MoveTo(0,Screen.Height div 2);
FullscreenCanvas.LineTo(1024,Screen.Height div 2);
end;
//以下代码实现定时在屏幕正中绘一个十字,一个正方形,一个圆形
procedure TForm1.Timer1Timer(Sender:
TObject);
var
MyCanvas:TCanvas;
DC:HDC;
begin
DC:=GetDC(0);
MyCanvas:=TCanvas.Create;
//MyCanvas.Brush.Color:=clblack;
//黑色填充色
MyCanvas.Brush.Style:=bsClear;
//无背景色
MyCanvas.Handle:=DC;
//MyCanvas.Brush.Bitmap:=image1.Picture.Bitmap;
MyCanvas.MoveTo(screen.Width
div 2,0);
MyCanvas.LineTo(screen.Width div
2,Screen.Height);
MyCanvas.MoveTo(0,screen.Height div
2);
MyCanvas.LineTo(screen.Width,screen.Height div
2);
MyCanvas.Rectangle(Screen.Width div 2-100,Screen.Height div
2-100,Screen.Width div 2+100,Screen.Height div 2+100);
//屏幕正中心绘制一个正方形
MyCanvas.Ellipse(Screen.Width div 2-100,Screen.Height div
2-100,Screen.Width div 2+100,Screen.Height div 2+100);
//屏幕正中心绘制一个圆形
MyCanvas.TextOut(720,300,'我测试再测试,测试直接在屏幕上写字的感觉!');
//在Canvas对象上添加文字
end;